In electrical motors electrical energy is transformed into mechanical energy or the other way around. Electrical energy has to be transferred from a stationary component into a moving one, which is done by a copper commutator in sliding contact with carbon brushes. Wear is occuring at surfaces of both components during dry sliding. For reduction of friction and wear rate solid lubricants are added to the carbon brush compositions. It was observed that during sliding a solid lubricant film is formed on the surface of the copper commutator. This transfer film has a limited life. After failure of the layer a new film is formed from the reservoir of the carbon brushes. Various solid lubricants in carbon brushes were tested. It was found, that certain solids form very thin layers with good adhesion on commutator surfaces, which improves tribological performance of both moving components. In particular wear rate, friction and noise is reduced significantly. This resulted in much longer service life of electrical motors for automotive applications.


    Access

    Access via TIB

    Check availability in my library


    Export, share and cite



    Title :

    Advancements of tribological performance of carbon brushes in electrical motors


    Additional title:

    Fortschritte auf dem Gebiet der tribologischen Wirksamkeit der Kohlebürsten in Elektromotoren


    Contributors:
    Groht, K. (author) / Heidenfelder, F. (author) / Holinski, R. (author)


    Publication date :

    2000


    Size :

    5 Seiten, 7 Bilder, 1 Tabelle, 3 Quellen


    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    Capacity limits of carbon brushes of traction motors

    Kasperowski, O. | Engineering Index Backfile | 1963



    Maintaining carbon brushes for good commutation

    Dobson, J.V. | Engineering Index Backfile | 1929


    Brushes

    Kalb, W.C. | Engineering Index Backfile | 1912


    Analysis of the Generation Mechanism of Chirp Noises in the Brushes of Blower Motors

    Mimura, Eiji / Oya, Takio / Sekiguchi, Tohru et al. | SAE Technical Papers | 1996